In Brief:
This warm beautiful weekend will be replaced by extreme cold and prolonged snow.
Forecast Discussion:
Before we look ahead to the next snow storm, we need to check on what fell on Wednesday. Longmont saw about 2.5-5 inches. Broomfield saw about 4-6 inches (Figure 1). We will warm this weekend to nearly 60F. Rapid melting should help clear roads and sidewalks in advance of our next snow (Figure 2).
The Longer Range Forecast:
Still looking at Figure 2- once the front hits around 2 p.m. Monday, the bottom drops out on temperatures. Figure 3 is a map of temperature departure from normal Tuesday noon. Areas around I-25 are 30-35 degrees below normal with areas around Cheyenne getting to 40 degrees colder than normal. I would not be surprised if the high on Tuesday doesn't break 10F.
This system will also be slow to cross the state. It looks like almost three days of snow showers are on the way. That is because of the size of the trough that is moving in (Figure 4). The smaller (or shorter) the trough is in the upper atmosphere, the quicker it moves, the larger, the slower. This is a pretty big wave this time.
It is too early for accurate snow totals, but 5-8 inches over three days is what you should start to plan for. More later and find your biggest coat!
